Preparation,characterization, and potential biomedical application of composite sponges based on collagen from silver carp skin

To reuse fish processing waste for biomedical materials, collagen (Col) was extracted from silver carp skin, and Col–chitosan (Ch) composite sponges were prepared by a freeze‐drying method. The atomic force microscopy and electrophoresis results suggest the Col might have been type I. To obtain the optimum conditions for the manufacture of the Col–Ch sponges, the characteristics of sponges composed of different ratios of Col to Ch with different crosslinkers were evaluated. Scanning electron microscopy showed that the sponges had an interconnected network structure with porosity. Infrared spectroscopy demonstrated that intermolecular crosslinkages between Col and Ch occurred. The swelling measurements implied that all of the sponges could bind an 18‐ to 36‐fold amount of distilled water and still maintain their form and stability. When the ratio of Col to Ch was higher than 1:0.25, the swelling and degradation rate decreased with increasing Ch. Cell proliferation, hemolysis, and hemostasis assay indicated that the sponges exhibited noncytotoxicity, biocompatibility, nonhemolysis, and hemostatic efficacy. Overall, we concluded that the optimal ratio of Col and Ch for the sponges was 1:0.25, and glutaraldehyde crosslinking was more suitable than 1‐ethyl‐3‐(3‐dimethylaminopropyl) carbodiimide hydrochloride. These results demonstrate the potential application of silver carp skin Col–Ch sponges for tissue engineering and wound dressing in non‐weight‐bearing tissue. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40998.     

Artificial neural network modelling of supercritical fluid CO2 extraction of polyunsaturated fatty acids from common carp (Cyprinus carpio L.) viscera

Common carp viscera, obtained from Tikveš Lake in Macedonia, was investigated as a possible source of polyunsaturated (PUFA) fatty acids. Supercritical fluid CO₂ extraction (SFE-CO₂) was employed for extraction of investigated bioactive components. The GC-FID analysis on the total extract obtained by supercritical fluid CO₂ extraction confirmed the assumption of presence of these bioactive components. A three layer artificial neural network was created for prediction and modelling of the extraction yield of polyunsaturated fatty acids from lyophilized viscera matrixes. Operating values of pressure, temperature, mass flow of CO₂ and extraction time were defined as input vectors to the ANN where PUFA extraction yield was considered as an output vector. Created ANN model provided adequate fitting of experimental data, with a correlation coefficient of 0.9968 for the entire data set. RSM-3D method was employed for mathematical modelling of the ANN output values as a function of operating variables and their interactions.     

Unraveling the biosynthesis of penicillenols by genome mining polyketide synthase and nonribosomal peptide synthetase gene clusters in Penicillium citrinum

Penicillenols belong to the family of tetramic acids with anticancer and antibacterial activities. Here, we report the discovery of the biosynthetic gene cluster (pnc) for penicillenol A₁ and E in Penicillium citrinum ATCC9849 by genome mining. We discover the pnc cluster based on the results of gene deletions in P. citrinum and gene cluster heterologous expression in Aspergillus nidulans. We also propose the assembly line of the polyketide synthase module in PncA with the reduction by PncB provides a highly reduce polyketide chain to be further linked with an l -threonine molecule and released from PncA to produce penicillenol E. Further formation of penicillenol A₁ requires the N-methylation of tetramic acid group by PncC. Our work deepens the understanding of the biosynthetic logic for N-methylated tetramic acids and contributes to the discovery of new penicillenols by genome mining.     

Low-cost synthesis of nano-hydroxyapatite from carp bone waste: Effect of calcination time and temperature

The aim of this study was to synthesize Hydroxyapatite (HA) from carp bone waste by calcination treatment. The effects of calcination temperature and time on crystallite size, crystallinity%, powder size and morphology, formed phases, and Ca/P ratio were analyzed. The XRD analyses indicated that for 1 h calcination time, HA was the only phase produced at all temperatures. However, for 5 h calcination time, temperatures other than 700ºC resulted in formation of TCP+HA. The HA obtained at 700ºC at both times had less crystallinity compared to other temperatures. Crystallite size increased by increase in temperature at 1 h calcination time. The smallest and largest particulate sizes were obtained at 800ºC for 1 h and 900ºC for 5 h, respectively. The Ca/P ratio close to theoretical value (1.67) was obtained for 5 h calcination time. Finally, the results showed the usefulness of the methodology used in natural HA production that can be used in orthopedics and dentistry.     

Structural Variation (SV) Markers in the Basidiomycete Volvariella volvacea and Their Application in the Construction of a Genetic Map

Molecular markers and genetic maps are useful tools in genetic studies. Novel molecular markers and their applications have been developed in recent years. With the recent advancements in sequencing technology, the genomic sequences of an increasingly great number of fungi have become available. A novel type of molecular marker was developed to construct the first reported linkage map of the edible and economically important basidiomycete Volvariella volvacea by using 104 structural variation (SV) markers that are based on the genomic sequences. Because of the special and simple life cycle in basidiomycete, SV markers can be effectively developed by genomic comparison and tested in single spore isolates (SSIs). This stable, convenient and rapidly developed marker may assist in the construction of genetic maps and facilitate genomic research for other species of fungi.     

磷石膏制硫酸联产水泥共性集成水泥粉磨新工艺

分析当前磷石膏制硫酸联产水泥粉磨工艺存在问题,介绍共性集成水泥粉磨新工艺的流程,论述了其创新点。共性集成水泥粉磨新工艺,克服了当前磷石膏联产水泥粉磨工艺的不足,生产成本低,产品强度高,具有较大的经济效益和环境效益。     

High throughput screening techniques in downstream processing: Preparation, characterization and optimization of aqueous two-phase systems

Merging aqueous two-phase systems (ATPS) with high throughput screening techniques is a promising approach which will certainly lead to a more frequent use of ATPS both in industry and in research. Despite the diverse possible applications of polymer-polymer or polymer-salt based extraction systems for biotechnological downstream processes the use of these systems has so far been limited. This is mostly due to the poor predictability and the large number of parameters influencing the partitioning result. Especially the large number of possible parameter combinations makes robotic high throughput screening an interesting alternative to manual experiments. Methods using the robotic pipetting station Tecan Freedom Evo 200 for the development of ATPS processes are described in this paper. Characteristic values such as tie lines, binodal curve and volumetric measurement are essential for the characterization of this kind of systems and can successfully be determined by the robotic system. Most important, the measurement of protein concentrations, partition coefficients and yields could also be automated and parallelized offering the possibility to design ATPS processes while screening a broad range of parameters with a high sample throughput.     

Development and Characterization of New Single Nucleotide Polymorphism Markers from Expressed Sequence Tags in Common Carp (Cyprinus carpio)

The common carp (Cyprinus carpio) is an important aquaculture fish worldwide but only limited single nucleotide polymorphism (SNP) markers are characterized from expressed sequence tags (ESTs) in this species. In this study, 1487 putative SNPs were bioinformatically mined from 14,066 online ESTs mainly from the European common carp, with the occurrence rate of about one SNP every 173 bp. One hundred and twenty-one of these SNPs were selected for validation using PCR fragment sequencing, and 48 out of 81 primers could amplify the expected fragments in the Chinese common carp genome. Only 26 (21.5%) putative SNPs were validated, however, 508 new SNPs and 68 indels were identified. The ratios of transitions to transversions were 1.77 for exon SNPs and 1.05 for intron SNPs. All the 23 SNPs selected for population tests were polymorphic, with the observed heterozygosity (Ho) ranging from 0.053 to 0.526 (mean 0.262), polymorphism information content (PIC) from 0.095 to 0.357 (mean 0.246), and 21 SNPs were in Hardy-Weinberg equilibrium. These results suggest that different common carp populations with geographic isolation have significant genetic variation at the SNP level, and these new EST-SNP markers are readily available for genetics and breeding studies in common carp.